--- plplot-5.9.9/lib/nn/CMakeLists.txt.orig	2011-10-13 02:43:01.000000000 +0200
+++ plplot-5.9.9/lib/nn/CMakeLists.txt	2011-11-18 21:55:24.366575267 +0100
@@ -46,7 +46,7 @@
     COMPILE_FLAGS "-I${QHULL_INCLUDE_DIRS}"
     INSTALL_NAME_DIR "${LIB_DIR}"
     )
-  target_link_libraries(csironn ${QHULL_LIBRARIES})
+  target_link_libraries(csironn ${QHULL_LIBRARIES} m)
   install(TARGETS csironn
     EXPORT export_plplot
     ARCHIVE DESTINATION ${LIB_DIR}